This invention relates to window shades, and in particular to the support rollers on which the shade material is wound. More particularly, the invention relates to window shade support rollers for the type of window shade which has come to be known as "manually sizable" or "handstrippable", and which includes a shade panel having a number of parallel, mutually spaced, scored (i.e., slit partially through), or other such "lines of weakness" along one or both lateral edges, by which the shade may be narrowed to a desired width by the consumer through exercise of merely manual efforts, i.e., in effect stripping off a particular amount of the shade fabric from one or both marginal edges along a selected scored line, or other "line of weakness", so as to end up with the particular width required for a particular window. Typically, the "lines of weakness" on the shade panel are formed by scoring or longitudinal slitting through a portion of the thickness of the shade panel material, thus establishing a straight and regular edge along which the material may subsequently be stripped, i.e., torn, the resulting edge after tearing having a very regular and smooth appearance appearing comparable to that of the original factory-cut edge.
In manually sizable window shades of the aforementioned type, the pre-scored shade panels must be mounted upon a support roller which in some way is adapted to being manually shortenable, so that the resulting narrowed shade panel is complemented by a correspondingly narrowed support roller, which corresponds in length to the width of the shade panel after the excess width has been removed. Various different types of shade rollers have heretofore been proposed for use with the pre-scored window shade material, which itself has been known for quite some time. Typically, all such rollers proposed heretofore have been the same as or very similar to the various window shade rollers previously in actual use, particularly those which have been used in conjunction with window shades that have been re-sized (narrowed) in more traditional ways at the point of purchase, e.g., by shade-cutting machines of the type which have long been known and used by window shade retailers.
For example, one such previously proposed manually sizable window shade construction (illustrated in the U.S. Patent to Ferguson, U.S. Pat. No. 4,006,770) utilizes the same basic telescoping metal tubular shade roller long used heretofore by other window shade companies, but proposes a two-step shade attachment procedure by which that portion of the window shade which is not pre-scored and not subject to subsequent hand-stripping is permanently attached to the main part of the telescoping support roller, whereas the scored portion of the shade is left unattached until the purchaser has narrowed the shade panel the requisite amount, by stripping off sufficient material, and has telescoped the support rod into itself sufficiently to make the overall length of the roller correspond to the width of the shortened shade panel, whereupon attachment of the shade panel to the roller is completed by adhering the previously unattached portion of the shade to the corresponding part of the telescoping roller.
In an earlier form of window shade product in which the scored shade material was initially suggested for use in the manually sizable manner generally alluded to above, the pre-scored shade material was merely used with a wood support roller which the consumer could foreshorten at home by use of a handsaw or the like, the manual stripping of the shade panel itself being the same as that described above.
Other forms of support roller proposed for use with the manually strippable, pre-scored window shade material have included tubular roller members of wound (e.g., convolute-wound) paper stock or the like, or fiberboardtype material, which have been partially pre-cut, as by perforating, etc., in incremental ring-like widths, in the same general manner as the window shade material, so as to provide segments which can be manually torn or broken off, thereby shortening the length of the roller (for example, see U.S. Pat. No. 4,102,384). While appearing to have possible economic advantages as well as functional advantages when compared to the telescoping metal rollers noted above and their two-step shade attachment requirements, such break-off rollers nonetheless involve significant disadvantages as well; for example, providing the numerous perforated break-off segments is labor intensive and expensive as a manufacturing process, and in actual practice the segments may well not be easy to break off, and may leave jagged or irregular edges. Further, and perhaps more importantly, the extent of the required pre-cutting substantially weakens the roller structure since it removes much of its beam strength. Thus, if such a paper or paperboard tube has been pre-cut sufficiently to provide reasonably easy manual break-off or other segmental shortening at home by the consumer, without tools, the resulting shade roller has probably been so weakened as to be in danger of failing or of being unsatisfactory during use, as when the window shade is pulled downward (unrolled) its full length by downward force loading applied to the center of the end-suspended roller by grasping the bottom edge of the shade panel and pulling downwardly. Such failure or malfunction is made even more likely by the stresses and strains imposed during the manual sizing operations done by the consumer, who grasps the pre-cut and weakened shade roller in both hands and subjects a significant portion of it to bending in order to tear off or break off the desired segment of the roller.